1. Field of the Invention
The present invention relates to an adapter for mixing and injection of preparations. More particularly, the present invention relates to an adapter for transferring a drug solution or solvent from a syringe to a vial including a dried medicine such as a powdered preparation or a solid preparation charged therein to mix them to prepare a dose of a mixed medical solution and for transferring the resultant medical solution in the vial to the syringe.
2. Description of Background Art
Freeze-dried medicines such as powdered preparations or solid preparations are generally stored in vials. In the prior art, such preparations are mixed with a solvent or drug solution, for example, by connecting a vial to a solvent vessel with a double-ended needle to form liquid communication between them, transferring the solvent from the solvent vessel to the vial to dissolve the dried medicine in the solvent, and collecting a certain amount of the resultant drug solution by a syringe through a needle attached thereto.
However, the above method takes a long time to fill the syringe with the resultant drug solution by suction because of a minor diameter of the needle to be used. Further, in order to avoid risk of an accident due to use of an edged metal needle, it is difficult to operate.
In order to solve such disadvantages, it has been proposed in Japanese patent unexamined publication JP-A 7-213585 to use an adapter for liquid transfer and injection, which is connectable to both a vial and a syringe and makes it possible to transfer the liquid without use of any syringe needle. This adapter comprises a cylindrical hub coaxially provided at one end thereof with a hollow puncture needle and at the opposite end with a tubular tip-fitting portion. At the peripheral part of the hub, there are provided a vial-fitting portion and a syringe-connecting portion, which are respectively coaxial to the puncture needle and the tip-fitting portion. The puncture needle is provided with a medicine channel communicated with the tip-fitting portion, and a gas channel being open to a vent hole with a filter for separation of microorganisms provided in the vial-fitting portion.
However, the above adapter for liquid transfer and injection has a danger of contamination in the medical solution with foreign substances due to coring which may occur by puncture of a rubber stopper with the puncture needle.
In view of the above circumstances, the present invention has been made to provide an adapter for mixing and injection of preparations, which makes it possible to remove foreign substances get into a medical solution in case of operation to dissolve a dose of a solid preparation in a solvent by use of the adapter.
According to the present invention, the above object is achieved by providing an adapter with a filter, in particular, by providing a connecting portion for attachment to the tip-fitting portion at a proximal end of a puncture needle and arranging a filter in the connecting portion. This makes it possible to provide a filter in the adapter with ease and certainty.
In other words, the present invention provides an adapter for mixing and injection of preparations comprising:
a vial-fitting portion having a top wall and a skirt portion;
a puncture needle passed through the top wall 11 of the vial-fitting portion 1 and integrated therewith, said puncture needle having a cutting edge on the side of said skirt; and
a tubular tip-fitting portion located coaxially to the puncture needle on the opposite side thereof to the top wall,
wherein said puncture needle has at a proximal end thereof a connecting portion for connection with the tip-fitting portion and a liquid passage which communicates with a lumen of the tip-fitting portion and is open to the cutting edge of the puncture needle, said connecting portion being provided at a liquid passage thereof with a filter.
In order to facilitate the transfer of liquid from a syringe to a vial or vice verse, the puncture needle may be provided with a gas passage running through the puncture needle and being open to the cutting edge while the connecting portion of the puncture needle may be provided with a vent hole having a filter for separation of microorganisms and being communicated with the gas passage. In this case, it is preferred to provide a check valve, which allows the gas to flow only in the direction of the gas passage, adjacent to the filter in the vent hole on the inside of the filter, so as to prevent the medical solution from flowing into the vent hole through the gas passage when the vial is reversed.
Further, in order to facilitate the attachment of the vial to the adapter, the vial-fitting portion may be provided in its skirt with one or more vertical slit.
Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.